Golf balls having reduced distance

ABSTRACT

Golf balls having core formulations including polybutadiene, butyl rubber, or a blend thereof, and low surface coverage dimple patterns are disclosed. The combination of low surface coverage with particular rubber formulations helps to reduce the flight of the ball while also providing improved aerodynamic consistency and maintaining the appearance of a high-performance trajectory.

FIELD OF THE INVENTION

The present disclosure relates generally to golf balls. Moreparticularly, the present disclosure relates to limited flight golfballs having low coverage dimple patterns and core formulations havinglow percentages of polybutadiene, butyl rubber, or blends thereof.

BACKGROUND OF THE INVENTION

The flight performance of a golf ball is affected by a variety offactors including the weight, size, materials, dimple pattern, andexternal shape of the golf ball. Golf ball manufacturers seek tomaximize aerodynamic efficiency and improve the performance of golfballs by adjusting the materials and construction of the ball as well asthe dimple pattern and dimple shape.

The aerodynamic forces acting on a golf ball are typically resolved intoorthogonal components of lift (FL) and drag (FD). Lift is defined as theaerodynamic force component acting perpendicular to the flight path. Itresults from a difference in pressure that is created by a distortion inthe air flow that results from the back spin of the ball. Due to theback spin, the top of the ball moves with the air flow, which delays theseparation to a point further aft. Conversely, the bottom of the ballmoves against the air flow, moving the separation point forward. Thisasymmetrical separation creates an arch in the flow pattern, requiringthe air over the top of the ball to move faster, and thus have lowerpressure than the air underneath the ball.

Drag is defined as the aerodynamic force component acting parallel tothe ball flight direction. As the ball travels through the air, the airsurrounding the ball has different velocities and, thus, differentpressures. The air exerts maximum pressure at the stagnation point onthe front of the ball. The air then flows over the sides of the ball andhas increased velocity and reduced pressure. The air separates from thesurface of the ball, leaving a large turbulent flow area with lowpressure, i.e., the wake. The difference between the high pressure infront of the ball and the low pressure behind the ball reduces the ballspeed and acts as the primary source of drag.

Recently, there has been an increased desire to manipulate theseaerodynamic forces to produce reduced-flight golf balls (i.e., golfballs that are designed to travel a distance that is shorter than thedistance traveled by standard golf balls). Advances in golf ballcompositions and dimple designs have caused high-performance golf ballsto exceed the maximum distance allowed by the United States GolfAssociation (USGA). Some industry experts have called for the USGA toroll back the distance standard for golf balls to preserve the game.

Golf ball manufacturers have developed ways to reduce the distancetraveled by the golf ball. For example, some manufacturers have createdinefficient dimple patterns or have modified the compositions of thegolf ball core to reduce the flight of the ball. Inefficient dimplepatterns with low surface coverages have been used for many years. Forexample, the Atti pattern, which is an octahedron pattern split intoeight concentric straight-line rows and covering 66 percent of the ball,was the predominant pattern utilized on golf balls for most of the20^(th) century. These dimple patterns were composed of substantiallyuniform dimples (for example, dimples having only one or two dimplediameters) and lacked aerodynamic efficiency. As dimple designers movedtoward patterns with increased surface coverages, many more dimple sizes(for example, dimple diameters) were needed to achieve increasedcoverages and improved aerodynamics, such as increased distance. Whilethese high-performance golf balls have improved aerodynamic consistency,the golf balls will not adhere to a shorter USGA maximum distance.

Accordingly, there remains a need to fine-tune the dimple patterns andthe golf ball compositions of these high-performance golf balls toreduce the flight distance, while also maintaining the appearance of ahigh-performance trajectory.

SUMMARY OF THE INVENTION

In some embodiments of the present disclosure, a golf ball is provided,the golf ball including a core layer including a rubber formulation ofpolybutadiene rubber, butyl rubber, or a blend thereof, and a coverlayer including a plurality of dimples disposed thereon, wherein thedimples are arranged in a tetrahedral pattern including foursubstantially identical dimple sections, wherein each dimple section isdefined by a spherical triangle, wherein the dimples in each of the foursubstantially identical dimple sections have a corresponding dimplediameter and a corresponding edge angle and the dimples in each of thefour substantially identical dimple sections include: (i) at least threedifferent dimple diameters including a minimum dimple diameter, amaximum dimple diameter, and at least one additional dimple diameter,wherein each of the at least three different dimple diameters range fromabout 0.030 inches to about 0.200 inches, and (ii) substantiallyidentical edge angles, and wherein the pattern has a surface coverage ofabout 65 percent or less and the pattern results in at least threedimple-free great circles on the golf ball, and wherein the surfacecoverage is related to the amount of polybutadiene rubber present in therubber formulation according to the following equation:

$\frac{BR}{1 - {SC}} \leq 2.$

where SC is the surface coverage in the decimal form of percentage and0<SC<1, and BR is the weight percent of polybutadiene rubber, in decimalform, based on the total weight of rubber in the rubber formulation and0≤BR≤1.

In this embodiment, the rubber formulation may include a blend ofpolybutadiene rubber and butyl rubber. In other embodiments, the golfball has a coefficient of restitution (COR) of about 0.780 or less, forexample, about 0.740 or less. In still other embodiments, the average ofall the edge angles (θ_(μ)) is related to the surface coverage accordingto the following equation:

88.8(SC)²−116.9(SC)+47.7≤θ_(μ)≤170.0(SC)²−242.5(SC)+106.6

where SC is the surface coverage in the decimal form of percentage and0<SC<1. In yet other embodiments, the golf ball has an initial velocityand the initial velocity is related to the surface coverage according tothe following equation:

$\frac{IV}{1 - {SC}} \leq 700$

where IV is the initial velocity in ft/sec and SC is the surfacecoverage in the decimal form of percentage and 0<SC<1.

In other embodiments of the present disclosure, a golf ball is provided,the golf ball including a core layer including a rubber formulation ofpolybutadiene rubber, butyl rubber, or a blend thereof, and a coverlayer including a plurality of dimples disposed thereon, wherein thedimples are arranged in a dipyramid pattern selected from the groupconsisting of triangular dipyramid, quadrilateral dipyramid, pentagonaldipyramid, and hexagonal dipyramid, the dipyramid pattern including six,eight, ten, or twelve substantially identical dimple sections, whereineach dimple section is defined by a spherical triangle having threevertices, wherein the dimples in each of the substantially identicaldimple sections have a corresponding dimple diameter and a correspondingedge angle and the dimples in each of the substantially identical dimplesections include: (i) at least three different dimple diametersincluding a minimum dimple diameter, a maximum dimple diameter, and atleast one additional dimple diameter, wherein each of the at least threedifferent dimple diameters range from about 0.030 inches to about 0.200inches, and (ii) substantially identical edge angles, and wherein thepattern has a surface coverage of about 65 percent or less and thepattern results in one dimple free great circle on the golf ball, andwherein the surface coverage is related to an amount of the rubberformulation according to the following equation:

$\frac{BR}{1 - {SC}} \leq 2.$

where SC is the surface coverage in the decimal form of percentage and0<SC<1, and BR is the weight percent of polybutadiene rubber, in decimalform, based on the total weight of rubber in the rubber formulation and0≤BR≤1.

In this embodiment, the rubber formulation may include a blend ofpolybutadiene rubber and butyl rubber in a ratio of about 30:70 to about70:30. In other embodiments, the golf ball has a coefficient ofrestitution (COR) of about 0.780 or less, for example, about 0.740 orless. In still other embodiments, the average of all the edge angles(θ_(μ)) is related to the surface coverage according to the followingequation:

88.8(SC)²−116.9(SC)+47.7≤θ_(μ)≤170.0(SC)²−242.5(SC)+106.6

where SC is the surface coverage in the decimal form of percentage and0<SC<1. In further embodiments, the golf ball includes an initialvelocity and the initial velocity is related to the surface coverageaccording to the following equation:

$\frac{IV}{1 - {SC}} \leq 600$

where IV is the initial velocity in ft/sec and SC is the surfacecoverage in the decimal form of percentage and 0<SC<1.

In still other embodiments of the present disclosure, a golf ball isprovided, the golf ball including a core layer including a rubberformulation of polybutadiene rubber, butyl rubber, or a blend thereof,and a cover layer including a plurality of dimples disposed thereon,wherein the dimples are arranged in an octahedral pattern includingeight substantially identical dimple sections, wherein each dimplesection is defined by a spherical triangle, wherein the dimples in eachof the eight substantially identical dimple sections have acorresponding dimple diameter and a corresponding edge angle and thedimples in each of the eight substantially identical dimple sectionsinclude: (i) at least three different dimple diameters including aminimum dimple diameter, a maximum dimple diameter, and at least oneadditional dimple diameter, wherein each of the at least three differentdimple diameters range from about 0.030 inches to about 0.200 inches,and (ii) substantially identical edge angles, and wherein the patternhas a surface coverage of about 65 percent or less and the patternresults in at least four dimple free great circles on the golf ball, andwherein the surface coverage is related to an amount of the rubberformulation according to the following equation:

$\frac{BR}{1 - {SC}} \leq 2.$

where SC is the surface coverage in the decimal form of percentage and0<SC<1, and BR is the weight percent of polybutadiene rubber, in decimalform, based on the total weight of rubber in the rubber formulation and0≤BR≤1.

In some embodiments, the golf ball has a coefficient of restitution andthe coefficient of restitution is related to the surface coverageaccording to the following equation:

$\frac{COR}{1 - {SC}} \leq 2.$

where COR is the coefficient of restitution and 0<COR<1, and SC is thesurface coverage in the decimal form of percentage and 0<SC<1. In otherembodiments, the average of all the edge angles (θ_(μ)) is related tothe surface coverage according to the following equation:

88.8(SC)²−116.9(SC)+47.7≤θ_(μ)≤170.0(SC)²−242.5(SC)+106.6

where SC is the surface coverage in the decimal form of percentage and0<SC<1. In still other embodiments, the rubber formulation includes ablend of polybutadiene rubber and butyl rubber in a ratio of about 40:60to about 60:40. In further embodiments, the golf ball includes aninitial velocity and the initial velocity is related to the surfacecoverage according to the following equation:

$\frac{IV}{1 - {SC}} \leq 500$

where IV is the initial velocity in ft/sec and SC is the surfacecoverage in the decimal form of percentage and 0<SC<1.

In yet other embodiments of the present disclosure, a golf ball isprovided, the golf ball including a core layer including a rubberformulation of polybutadiene rubber, butyl rubber, or a blend thereof,and a cover layer including a plurality of dimples disposed thereon, aplurality of dimples disposed thereon, wherein the dimples are arrangedin an icosahedral pattern including twenty substantially identicaldimple sections, wherein each dimple section is defined by a sphericaltriangle, wherein the dimples in each of the twenty substantiallyidentical dimple sections have a corresponding dimple diameter and acorresponding edge angle and the dimples in each of the twentysubstantially identical dimple sections include: (i) at least fourdifferent dimple diameters including a minimum dimple diameter, amaximum dimple diameter, and at least two additional dimple diameters,wherein each of the at least four different dimple diameters range fromabout 0.030 inches to about 0.200 inches, and (ii) substantiallyidentical edge angles, and wherein the pattern has a surface coverage ofabout 65 percent or less and the pattern results in at least five dimplefree great circles on the golf ball, and wherein the surface coverage isrelated to an amount of the rubber formulation according to thefollowing equation:

$\frac{BR}{1 - {SC}} \leq 2.$

where SC is the surface coverage in the decimal form of percentage and0<SC<1, and BR is the weight percent of polybutadiene rubber, in decimalform, based on the total weight of rubber in the rubber formulation and0≤BR≤1.

In some embodiments, the rubber formulation includes butyl rubber. Inother embodiments, the rubber formulation includes a blend ofpolybutadiene rubber and butyl rubber in a ratio of about 30:70 to about70:30. In still other embodiments, the golf ball has a coefficient ofrestitution and the coefficient of restitution is related to the surfacecoverage according to the following equation:

$\frac{COR}{1 - {SC}} \leq 1.75$

where COR is the coefficient of restitution and 0<COR<1, and SC is thesurface coverage in the decimal form of percentage and 0<SC<1. Infurther embodiments, the golf ball has an initial velocity of about 246ft/sec or less, for example, about 240 ft/sec or less.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the invention can be ascertained fromthe following detailed description that is provided in connection withthe drawings described below:

FIG. 1 is a schematic diagram illustrating a method for measuring thediameter of a dimple;

FIG. 2 is a graphical representation of the relationship between edgeangle and surface coverage according to one embodiment of the presentdisclosure; and

FIG. 3 is a graphical representation of the relationship between averagedimple volume and surface coverage according to another embodiment ofthe present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art of this disclosure. It will be furtherunderstood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andshould not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein. Well known functions or constructions maynot be described in detail for brevity or clarity.

The terms “about” and “approximately” shall generally mean an acceptabledegree of error or variation for the quantity measured given the natureor precision of the measurements. Numerical quantities given in thisdescription are approximate unless stated otherwise, meaning that theterm “about” or “approximately” can be inferred when not expresslystated.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well (i.e., at least one of whatever the article modifies),unless the context clearly indicates otherwise.

The present disclosure provides reduced-flight golf balls. That is, golfballs designed to travel a distance that is shorter than the distancetraveled by current performance balls. The distance that a golf ballwill travel upon impact by a golf club is a function of the coefficientof restitution (COR), the weight, and the aerodynamic characteristics ofthe ball, which among other things are affected by one or more factors,such as the size, dimple coverage, dimple size, dimple shape, andcomposition of the various layers in the golf ball including the core.The golf balls of the present disclosure include center components, suchas core and intermediate layers, formed from formulations having a lowpercentage of polybutadiene or butyl rubber and covers with dimplepatterns designed to limit the aerodynamic performance of the golf ball(for example, a low surface coverage dimple pattern). The novel golfballs achieve a reduction in overall distance when compared to aconventional golf ball hit under the same conditions. Advantageously,the combination of a dimple pattern with low surface coverage and a corewith a percentage of butyl rubber restricts flight while also providingaerodynamic consistency and an appearance of a high-performancetrajectory.

Dimple Patterns

In some embodiments, the golf balls of the present disclosure utilizedimple patterns designed to achieve a reduction in overall distance whencompared to a conventional golf ball. One way to achieve such a dimplepattern is to utilize a dimple pattern having a low percentage ofsurface coverage. As used herein, “surface coverage” refers to thepercentage of the ball surface that has been removed by the formation ofdimples. In other words, the surface coverage is the surface area of asphere having the diameter of the golf (D_(ball)) minus the surface areaof the fret area of the golf ball. By reducing the surface coverage ofdimples on the ball, the flight and distance of the golf ball can bereduced.

Surface coverage may be calculated using equation (I):

$\begin{matrix}{{{{Surface}{Coverage}} = \frac{\sum_{i = 1}^{n}{\pi\left( {r_{i}^{2} + h_{i}^{2}} \right)}}{4{\pi\left( \frac{D_{ball}}{2} \right)}^{2}}},} & (I)\end{matrix}$

where n is the number of dimples on the ball, r is the dimple plan shaperadius (equal to the dimple diameter/2), and h is the cap height.

In one embodiment, the dimple patterns utilized with a golf ball of thepresent disclosure have a surface coverage of less than about 70percent. In another embodiment, golf balls according to the presentinvention have a dimple pattern with a surface coverage of less thanabout 65 percent. In another embodiment, the dimple patterns utilizedwith the golf balls of the present disclosure have a surface coverage ofless than about 60 percent. In still another embodiment, golf balls ofthe present invention employ dimple patterns having a surface coverageof less than about 50 percent. In yet another embodiment, the dimplepatterns utilized with golf balls in accordance with the presentdisclosure have a surface coverage of less than about 40 percent. Inanother embodiment, the dimple patterns utilized with golf balls inaccordance with the present disclosure have a surface coverage of lessthan about 30 percent. In still another embodiment, golf balls of thepresent invention employ dimple patterns having a surface coverage ofless than about 20 percent. In yet another embodiment, the dimplepatterns utilized with the golf balls of the present disclosure have asurface coverage of about 15 percent.

The dimple patterns may be arranged in any type of layout that resultsin a correspondingly low dimple surface coverage (for instance, asurface coverage of less than 70 percent, and preferably less than 65percent). As will be discussed in more detail below, suitable dimplelayouts for golf balls made in accordance with the present disclosureinclude, but are not limited to, tetrahedral layouts, such as thosedescribed in U.S. application Ser. No. 16/953,507, filed on Nov. 20,2020, the entire disclosure of which is incorporated herein byreference; dipyramid layouts, such as those described in U.S.application Ser. No. 16/953,540, filed on Nov. 20, 2020, the entiredisclosure of which is incorporated herein by reference; octahedrallayouts, such as those described in U.S. application Ser. No.16/953,552, filed on Nov. 20, 2020, the entire disclosure of which isincorporated herein by reference; and icosahedral layouts, such as thosedescribed in U.S. application Ser. No. 16/953,528, filed on Nov. 20,2020, the entire disclosure of which is incorporated herein byreference.

Tetrahedral Dimple Patterns

In one embodiment, golf ball dimple patterns utilized with golf ballsaccording to the present disclosure are arranged in a tetrahedrallayout. The golf ball dimple patterns are arranged in a tetrahedrallayout such that there are four identical sections on the golf ball. Inone embodiment, each section is in the shape of a spherical triangle. Asused herein, “spherical triangle” refers to a figure formed on thesurface of a sphere by three circular arcs intersecting pairwise atthree vertices. The three circular arcs each represent an edge of thespherical triangle.

The dimples may be located entirely within a dimple section. Forexample, in one embodiment, the dimples may be arranged within the edgesof the spherical triangle such that no dimples intersect an edge of thespherical triangle. In another embodiment, dimples may be shared betweentwo or more dimples sections. In one aspect of this embodiment, for eachdimple that is not located entirely within a dimple section, thecentroid of the dimple is located along a side edge or at one or morevertices of the spherical triangle. In another aspect of thisembodiment, dimples shared between two sections may include dimples thatare positioned such that the centroid of the dimple does not lie along aside edge. For purposes of the present disclosure, the “centroid” of thedimple refers to the center of the dimple.

In one embodiment, the dimple pattern within each of the four identicaldimple sections may be arranged such that one or more dimples intersectan edge of the spherical triangle. In a particular aspect of thisembodiment, the edge intersected by the one or more dimples runs throughthe centroid of the dimple such that half of the dimple is locatedwithin one spherical triangle and the other half is located withinanother spherical triangle. In another aspect of this embodiment, theedge intersected by one or more dimples does not run through thecentroid of the dimple. That is, less than half of the dimple is locatedwithin one spherical triangle and more than half of the dimple islocated within an adjacent spherical triangle. In one embodiment, thedimple pattern within each of the four identical dimple sectionsincludes at least three dimples that intersect an edge of the sphericaltriangle. In another embodiment, the dimple pattern within each of thefour identical dimple sections includes at least six dimples thatintersect an edge of the spherical triangle. In another embodiment, thedimple pattern within each of the four identical dimple sectionsincludes at least twelve dimples that intersect an edge of the sphericaltriangle. In another embodiment, the dimple pattern within each of thefour identical dimple sections includes at least fifteen dimples thatintersect an edge of the spherical triangle.

In another embodiment, the tetrahedral dimple patterns may be arrangedsuch that a dimple lies at one or more vertices of the sphericaltriangle. In this embodiment, the centroid of the dimple is located atthe vertex of the spherical triangle and a portion of the dimple islocated within three of the spherical triangles. That is, the dimplelocated at the vertex of the spherical triangle may be centered on thevertices of the spherical triangles. The dimple patterns of the presentdisclosure may include a dimple located at a single vertex of thespherical triangle. In another embodiment, the dimple patterns mayinclude a dimple located at each of two vertices of the sphericaltriangle. In still another embodiment, the dimple patterns may include adimple located at each of the three vertices of the spherical triangle.

The dimple patterns arranged in each of the dimple sections, forexample, in each of the four spherical triangles, are substantiallyidentical to each other. For purposes of the present disclosure, dimplepatterns are “substantially identical” if they have substantially thesame dimple arrangement (i.e., the relative positions of each of thedimples' centroids are about the same) and substantially the same dimplecharacteristics (e.g., plan shape, cross-sectional shape, diameter, edgeangle). Thus, for each dimple located entirely within a particulardimple section, for example, a particular spherical triangle, there is acorresponding dimple in each of the other three dimple sections. Fordimples having a centroid located along an edge of the dimple section,there is a corresponding dimple located along the same edge in the otherthree dimple sections. For dimples located at the one or more verticesof the dimple sections, these dimples are shared between the otherdimple sections.

The dimple patterns within each dimple section, for example, within eachof the four spherical triangles, include dimples having varying dimplediameters. In one embodiment, each dimple pattern has at least threedifferent dimple diameters, including a minimum diameter dimple, amaximum diameter dimple, and at least one additional diameter dimple.For purposes of the present disclosure, dimples having substantiallydifferent diameters include dimples on a finished ball having respectivediameters that differ by 0.005 inches or more. In another embodiment,each dimple pattern has at least four different dimple diameters,including a minimum diameter dimple, a maximum diameter dimple, and atleast two additional diameter dimples. In still another embodiment, eachdimple pattern has at least five different dimple diameters, including aminimum diameter dimple, a maximum diameter dimple, and at least threeadditional diameter dimples. In yet another embodiment, each dimplepattern has at least six different dimple diameters, including a minimumdiameter dimple, a maximum diameter dimple, and at least four additionaldiameter dimples.

In one embodiment, each dimple has a dimple diameter of about 0.030inches to about 0.200 inches. In another embodiment, each dimple has adimple diameter of about 0.050 inches to about 0.180 inches. In stillanother embodiment, each dimple has a dimple diameter of about 0.070inches to about 0.160 inches. In yet another embodiment, each dimple hasa dimple diameter of about 0.090 inches to about 0.140 inches.

The minimum and maximum differences between any two dimple diameterswithin a dimple section may vary. In one embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.030 inches or more. In another embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.040 inches or more. In other embodiments, the maximum differencebetween any two dimple diameters within a dimple section is about 0.055inches or less. In another embodiment, the maximum difference betweenany two dimple diameters within a dimple section is about 0.045 inchesor less. For instance, the difference between any two dimple diameterswithin each dimple section is about 0.030 inches to about 0.055 inches.

In some embodiments, the tetrahedral dimple pattern includes at leastone dimple intersecting an edge of the dimple section. In thisembodiment, at least one dimple having the minimum dimple diameterintersects the edge of the dimple section. In another embodiment, atleast one dimple having the maximum dimple diameter intersects the edgeof the dimple section. In still another embodiment, at least one dimplehaving neither the minimum nor maximum dimple diameter intersects theedge of the dimple section. Additionally, in some embodiments, thedimple pattern includes at least one dimple lying at a vertex of thedimple section. In this aspect, at least one dimple having the maximumdimple diameter is located at a vertex of the dimple section.

In one embodiment, the tetrahedral dimple patterns disclosed herein maybe symmetric. For example, the dimple patterns within each dimplesection may be rotationally symmetric about the central point of eachdimple section. That is, the dimple patterns may have three-wayrotational symmetry about an axis connecting the center of the golf balland the central point of the dimple section. In another embodiment, thedimple patterns may have mirror symmetry about a central plane of eachdimple section, where the central plane is a plane containing the centerof the golf ball, the central point of the corresponding dimple section,and one vertex of the corresponding dimple section.

In one embodiment, the dimples should be arranged within each dimplesection such that the outer surface of the golf ball has dimple freegreat circles. A golf ball having a “dimple free great circle” refers toa golf ball having an outer surface that contains a great circle whichdoes not intersect any dimples. In mathematical terms, every dimple freegreat circle follows a path on the surface of a golf ball having a givenwidth, and within the given width, there exists an infinite number ofgreat circles. However, for purposes of the present disclosure, eachdimple free great circle traverses a different dimple free path in thedimple pattern than another dimple free great circle.

In one embodiment, the dimples may be arranged within each of the fourdimple sections such that there are three dimple-free great circles onthe outer surface of the golf ball. In another embodiment, the dimplesmay be arranged within each dimple section such that there are twodimple-free great circles on the outer surface of the golf ball. In yetanother embodiment, the dimples may be arranged within each dimplesection such that there is one dimple-free great circle on the outersurface of the golf ball.

The dimples may be positioned within each of the four dimple sectionsaccording to any packing method known in the art so long as the dimplesections are substantially identical and meet the symmetry and surfacecoverage requirements discussed herein. For example, the dimples may bearranged within each dimple section according to the methods describedin pending U.S. application Ser. No. 16/785,624, filed on Feb. 9, 2020,the entire disclosure of which is incorporated herein by reference.

Dipyramid Dimple Patterns

In another embodiment, dimple patterns utilized with the golf ballsaccording to the present disclosure are arranged in dipyramid layouts.According to the dipyramid layouts, there are two identical hemisphereson the golf ball separated by an equator. Each hemisphere may includethree, four, five, or six triangular segments such that there are six,eight, ten, or twelve identical sections, respectively, on the golfball. In one embodiment, each section is in the shape of a sphericaltriangle. The three circular arcs each represent an edge of thespherical triangle. In some embodiments, each spherical triangle has abase edge located at the equator of the golf ball and two side edgesthat run longitudinally from the base edge to the pole of thehemisphere. A spherical triangle in the northern hemisphere may bejoined with a spherical triangle in the southern hemisphere at theirbase edges to form a “dipyramid.”

In one embodiment, the golf ball dimple patterns may be arranged in atriangular dipyramid layout such that there are three sphericaltriangles on each of the two hemispheres of the golf ball.

In this embodiment, the triangular dipyramid layout includes a total ofsix identical dimple sections on the golf ball. In another embodiment,the golf ball dimple patterns may be arranged in a quadrilateraldipyramid layout such that there are four spherical triangles on each ofthe two hemispheres of the golf ball. In this embodiment, thequadrilateral dipyramid layout includes a total of eight identicaldimple sections on the golf ball. In still another embodiment, the golfball dimple patterns may be arranged in a pentagonal dipyramid layoutsuch that there are five spherical triangles on each of the twohemispheres of the golf ball. In this embodiment, the pentagonaldipyramid layout includes a total of ten identical dimple sections onthe golf ball. In yet another embodiment, the golf ball dimple patternsmay be arranged in a hexagonal dipyramid layout such that there are sixspherical triangles on each of the two hemispheres of the golf ball. Inthis embodiment, the hexagonal dipyramid layout includes a total oftwelve identical dimple sections on the golf ball.

In one embodiment, the dimples may be located entirely within a dimplesection. For example, the dimples may be arranged within the edges ofthe spherical triangle such that no dimples intersect an edge of thespherical triangle. In another embodiment, dimples may be shared betweentwo or more dimples sections. In one aspect of this embodiment, for eachdimple that is not located entirely within a dimple section, thecentroid of the dimple is located along a side edge or at one or morevertices of the spherical triangle. In another aspect of thisembodiment, dimples shared between two sections may include dimples thatare positioned such that the centroid of the dimple does not lie along aside edge. For purposes of the present disclosure, the “centroid” of thedimple refers to the center of the dimple. In other embodiments, thebase edges of the dimple sections are defined such that no dimplesintersect the base edge.

In one embodiment, the dimple pattern within each of the dimple sectionsmay be arranged such that one or more dimples intersect a side edge ofthe spherical triangle. In a particular aspect of this embodiment, theside edge intersected by the one or more dimples runs through thecentroid of the dimple such that half of the dimple is located withinone spherical triangle and the other half is located within anotherspherical triangle. In another aspect of this embodiment, the side edgeintersected by one or more dimples does not run through the centroid ofthe dimple. That is, less than half of the dimple is located within onespherical triangle and more than half of the dimple is located within anadjacent spherical triangle. In one embodiment, the dimple patternwithin each of the dimple sections includes at least three dimples thatintersect a side edge of the spherical triangle. In another embodiment,the dimple pattern within each of the dimple sections includes at leastsix dimples that intersect a side edge of the spherical triangle. Inanother embodiment, the dimple pattern within each of the dimplesections includes at least twelve dimples that intersect a side edge ofthe spherical triangle. In another embodiment, the dimple pattern withineach of the dimple sections includes at least fifteen dimples thatintersect a side edge of the spherical triangle.

In another embodiment, the dipyramid dimple patterns may be arrangedsuch that a dimple lies at one or more vertices of the sphericaltriangle. In this embodiment, the centroid of the dimple is located atthe vertex of the spherical triangle and a portion of the dimple islocated within the other spherical triangles. That is, the dimplelocated at the vertex of the spherical triangle may be centered on thevertices of the spherical triangles. The dimple patterns of the presentdisclosure may include a dimple located at a single vertex of thespherical triangle. In another embodiment, the dimple patterns mayinclude a dimple located at each of two vertices of the sphericaltriangle. In still another embodiment, the dimple patterns may include adimple located at each of the three vertices of the spherical triangle.

The dimple patterns arranged in each of the dimple sections, forexample, in each of the spherical triangles, are substantially identicalto each other. For purposes of the present disclosure, dimple patternsare “substantially identical” if they have substantially the same dimplearrangement (i.e., the relative positions of each of the dimples'centroids are about the same) and substantially the same dimplecharacteristics (e.g., plan shape, cross-sectional shape, diameter, edgeangle). Thus, for each dimple located entirely within a particulardimple section, for example, a particular spherical triangle, there is acorresponding dimple in each of the other dimple sections. For dimpleshaving a centroid located along an edge of the dimple section, there isa corresponding dimple located along the same edge in the other dimplesections. For dimples located at the one or more vertices of the dimplesections, these dimples are shared between the other dimple sections.

The dimple patterns within each dimple section, for example, within eachspherical triangle, include dimples having varying dimple diameters. Inone embodiment, each dimple pattern has at least two different dimplediameters, including a minimum diameter dimple and a maximum diameterdimple. For example, the triangular and hexagonal dipyramid layoutsdisclosed herein may include dimple patterns having at least twodifferent dimple diameters. For purposes of the present disclosure,dimples having substantially different diameters include dimples on afinished ball having respective diameters that differ by 0.005 inches ormore. In another embodiment, each dimple pattern has at least threedifferent dimple diameters, including a minimum diameter dimple, amaximum diameter dimple, and at least one additional diameter dimple.For instance, the quadrilateral and pentagonal dipyramid layoutsdisclosed herein may include dimple patterns having at least threedifferent dimple diameters. In another embodiment, each dimple patternhas at least four different dimple diameters, including a minimumdiameter dimple, a maximum diameter dimple, and at least two additionaldiameter dimples. In still another embodiment, each dimple pattern hasat least five different dimple diameters, including a minimum diameterdimple, a maximum diameter dimple, and at least three additionaldiameter dimples. In yet another embodiment, each dimple pattern has atleast six different dimple diameters, including a minimum diameterdimple, a maximum diameter dimple, and at least four additional diameterdimples. In still another embodiment, each dimple pattern has at leastseven different dimple diameters, including a minimum diameter dimple, amaximum diameter dimple, and at least five additional diameter dimples.

In one embodiment, each dimple has a dimple diameter of about 0.030inches to about 0.200 inches. In another embodiment, each dimple has adimple diameter of about 0.050 inches to about 0.180 inches. In stillanother embodiment, each dimple has a dimple diameter of about 0.070inches to about 0.160 inches. In yet another embodiment, each dimple hasa dimple diameter of about 0.090 inches to about 0.140 inches. In someembodiments, the minimum dimple diameter is less than 0.100 inches. Forinstance, the minimum dimple diameter may be about 0.030 inches to about0.100 inches. In another embodiment, the minimum dimple diameter may beabout 0.050 inches to about 0.090 inches.

The minimum and maximum differences between any two dimple diameterswithin a dimple section may vary. In one embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.030 inches or more. In another embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.040 inches or more. In other embodiments, the maximum differencebetween any two dimple diameters within a dimple section is about 0.080inches or less. In another embodiment, the maximum difference betweenany two dimple diameters within a dimple section is about 0.065 inchesor less. In still another embodiment, the maximum difference between anytwo dimple diameters within a dimple section is about 0.055 inches orless. In another embodiment, the maximum difference between any twodimple diameters within a dimple section is about 0.045 inches or less.For instance, the difference between any two dimple diameters withineach dimple section is about 0.030 inches to about 0.080 inches.

In some embodiments, the dimple pattern includes at least one dimpleintersecting a side edge of the dimple section. In this embodiment, atleast one dimple having the minimum dimple diameter intersects the sideedge of the dimple section. In another embodiment, at least one dimplehaving the maximum dimple diameter intersects the side edge of thedimple section. In still another embodiment, at least one dimple havingneither the minimum nor maximum dimple diameter intersects the side edgeof the dimple section. Additionally, in some embodiments, the dimplepattern includes at least one dimple lying at a vertex of the dimplesection. In one embodiment, at least one dimple having the maximumdimple diameter is located at a vertex of the dimple section. In anotherembodiment, at least one dimple having the minimum dimple diameter islocated at a vertex of the dimple section. In still another embodiment,at least one dimple having neither the minimum nor maximum dimplediameter is located at a vertex of the dimple section.

In one embodiment, the dipyramid dimple patterns disclosed herein may besymmetric. For example, the dimple patterns within each dimple sectionmay be rotationally symmetric about the central point of each dimplesection. That is, the dimple patterns may have three-way rotationalsymmetry about an axis connecting the center of the golf ball and thecentral point of the dimple section. In another embodiment, the dimplepatterns may have mirror symmetry about a central plane of each dimplesection, where the central plane is a plane containing the center of thegolf ball, the central point of the corresponding dimple section, andone vertex of the corresponding dimple section. In still otherembodiments, the dimple patterns disclosed herein are not rotationallysymmetric. For example, the triangular and hexagonal dipyramid dimplepatterns may not be rotationally symmetric about the central point ofeach dimple section.

In one embodiment, the dimples may be arranged within each dimplesection such that there are more than three dimple free great circles onthe outer surface of the golf ball. For example, the dimples may bearranged within each dimple section such that there are four dimple freegreat circles on the outer surface of the golf ball. In otherembodiments, the dimples may be arranged within each dimple section suchthat there is one dimple free great circle on the outer surface of thegolf ball. In still other embodiments, the dimples may be arrangedwithin each dimple section such that there are no dimple free greatcircles on the outer surface of the golf ball.

The dimples may be positioned within each dimple section according toany packing method known in the art so long as the dimple sections aresubstantially identical and meet the symmetry and surface coveragerequirements discussed herein. For example, the dimples may be arrangedwithin each dimple section according to the methods described in U.S.Pat. No. 10,183,195, issued on Jan. 22, 2019; U.S. Pat. No. 7,503,856,issued on Mar. 17, 2009; pending U.S. application Ser. No. 16/587,298,filed on Sep. 30, 2019; and pending U.S. application Ser. No.16/587,321, filed on Sep. 30, 2019, the entire disclosures of which areincorporated herein by reference.

Octahedral Dimple Patterns

In still another embodiment, golf balls of the present invention includedimple patterns that have an octahedral layout. The golf ball dimplepatterns are arranged in an octahedral layout such that there are eightidentical sections on the golf ball. In one embodiment, each section isin the shape of a spherical triangle. The three circular arcs eachrepresent an edge of the spherical triangle.

The dimples may be located entirely within a dimple section. Forexample, in one embodiment, the dimples may be arranged within the edgesof the spherical triangle such that no dimples intersect an edge of thespherical triangle. In another embodiment, dimples may be shared betweentwo or more dimples sections. In one aspect of this embodiment, for eachdimple that is not located entirely within a dimple section, thecentroid of the dimple is located along a side edge or at one or morevertices of the spherical triangle. In another aspect of thisembodiment, dimples shared between two sections may include dimples thatare positioned such that the centroid of the dimple does not lie along aside edge. For purposes of the present disclosure, the “centroid” of thedimple refers to the center of the dimple.

In one embodiment of the present invention, the dimple pattern withineach of the eight identical dimple sections may be arranged such thatone or more dimples intersect an edge of the spherical triangle. In aparticular aspect of this embodiment, the edge intersected by the one ormore dimples runs through the centroid of the dimple such that half ofthe dimple is located within one spherical triangle and the other halfis located within another spherical triangle. In another aspect of thisembodiment, the edge intersected by one or more dimples does not runthrough the centroid of the dimple. That is, less than half of thedimple is located within one spherical triangle and more than half ofthe dimple is located within an adjacent spherical triangle. In oneembodiment, the dimple pattern within each of the eight identical dimplesections includes at least three dimples that intersect an edge of thespherical triangle. In another embodiment, the dimple pattern withineach of the eight identical dimple sections includes at least sixdimples that intersect an edge of the spherical triangle. In anotherembodiment, the dimple pattern within each of the eight identical dimplesections includes at least twelve dimples that intersect an edge of thespherical triangle. In another embodiment, the dimple pattern withineach of the eight identical dimple sections includes at least fifteendimples that intersect an edge of the spherical triangle.

In another embodiment, the octahedral dimple patterns may be arrangedsuch that a dimple lies at one or more vertices of the sphericaltriangle. In this embodiment, the centroid of the dimple is located atthe vertex of the spherical triangle and a portion of the dimple islocated within four of the spherical triangles. That is, the dimplelocated at the vertex of the spherical triangle may be centered on thevertices of the spherical triangles. The dimple patterns of the presentdisclosure may include a dimple located at a single vertex of thespherical triangle. In another embodiment, the dimple patterns mayinclude a dimple located at each of two vertices of the sphericaltriangle. In still another embodiment, the dimple patterns may include adimple located at each of the three vertices of the spherical triangle.

The dimple patterns arranged in each of the dimple sections, forexample, in each of the eight spherical triangles, are substantiallyidentical to each other. For purposes of the present disclosure, dimplepatterns are “substantially identical” if they have substantially thesame dimple arrangement (i.e., the relative positions of each of thedimples' centroids are about the same) and substantially the same dimplecharacteristics (e.g., plan shape, cross-sectional shape, diameter, edgeangle). Thus, for each dimple located entirely within a particulardimple section, for example, a particular spherical triangle, there is acorresponding dimple in each of the other seven dimple sections. Fordimples having a centroid located along an edge of the dimple section,there is a corresponding dimple located along the same edge in the otherseven dimple sections. For dimples located at the one or more verticesof the dimple sections, these dimples are shared between the otherdimple sections.

The dimple patterns within each dimple section, for example, within eachof the eight spherical triangles, include dimples having varying dimplediameters. In one embodiment, each dimple pattern has at least threedifferent dimple diameters, including a minimum diameter dimple, amaximum diameter dimple, and at least one additional diameter dimple.For purposes of the present disclosure, dimples having substantiallydifferent diameters include dimples on a finished ball having respectivediameters that differ by 0.005 inches or more. In another embodiment,each dimple pattern has at least four different dimple diameters,including a minimum diameter dimple, a maximum diameter dimple, and atleast two additional diameter dimples. In still another embodiment, eachdimple pattern has at least five different dimple diameters, including aminimum diameter dimple, a maximum diameter dimple, and at least threeadditional diameter dimples. In yet another embodiment, each dimplepattern has at least six different dimple diameters, including a minimumdiameter dimple, a maximum diameter dimple, and at least four additionaldiameter dimples.

In one embodiment, each dimple has a dimple diameter of about 0.030inches to about 0.200 inches. In another embodiment, each dimple has adimple diameter of about 0.050 inches to about 0.180 inches. In stillanother embodiment, each dimple has a dimple diameter of about 0.070inches to about 0.160 inches. In yet another embodiment, each dimple hasa dimple diameter of about 0.090 inches to about 0.140 inches. In someembodiments, the minimum dimple diameter is less than 0.100 inches. Forinstance, the minimum dimple diameter may be about 0.030 inches to about0.100 inches. In another embodiment, the minimum dimple diameter may beabout 0.050 inches to about 0.090 inches.

The minimum and maximum differences between any two dimple diameterswithin a dimple section may vary. In one embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.030 inches or more. In another embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.040 inches or more. In other embodiments, the maximum differencebetween any two dimple diameters within a dimple section is about 0.075inches or less. In another embodiment, the maximum difference betweenany two dimple diameters within a dimple section is about 0.055 inchesor less. In still another embodiment, the maximum difference between anytwo dimple diameters within a dimple section is about 0.045 inches orless. For instance, the difference between any two dimple diameterswithin each dimple section is about 0.030 inches to about 0.075 inches.

In some embodiments, the dimple pattern includes at least one dimpleintersecting an edge of the dimple section. In this embodiment, at leastone dimple having the minimum dimple diameter intersects the edge of thedimple section. In another embodiment, at least one dimple having themaximum dimple diameter intersects the edge of the dimple section. Instill another embodiment, at least one dimple having the minimum dimplediameter and at least one dimple having the maximum dimple diameterintersect the edge of the dimple section. In still another embodiment,at least one dimple having neither the minimum nor maximum dimplediameter intersects the edge of the dimple section. Additionally, insome embodiments, the dimple pattern includes at least one dimple lyingat a vertex of the dimple section. In this aspect, at least one dimplehaving the minimum or maximum dimple diameter is located at a vertex ofthe dimple section. In another embodiment, at least one dimple havingneither the minimum nor maximum dimple diameter is located at a vertexof the dimple section.

In one embodiment, the octahedral dimple patterns disclosed herein maybe symmetric. For example, the dimple patterns within each dimplesection may be rotationally symmetric about the central point of eachdimple section. That is, the dimple patterns may have three-wayrotational symmetry about an axis connecting the center of the golf balland the central point of the dimple section. In another embodiment, thedimple patterns may have mirror symmetry about a central plane of eachdimple section, where the central plane is a plane containing the centerof the golf ball, the central point of the corresponding dimple section,and one vertex of the corresponding dimple section.

In one embodiment, the dimples may be arranged within each of the eightdimple sections such that there are more than three dimple free greatcircles on the outer surface of the golf ball. For instance, the dimplesmay be arranged within each dimple section such that there are fourdimple free great circles on the outer surface of the golf ball. In yetanother embodiment, the dimples may be arranged within each dimplesection such that there are five or more dimple free great circles onthe outer surface of the golf ball.

The dimples may be positioned within each of the eight dimple sectionsaccording to any packing method known in the art so long as the dimplesections are substantially identical and meet the symmetry and surfacecoverage requirements discussed herein. For example, the dimples may bearranged within each dimple section according to the methods describedin U.S. Pat. No. 10,532,252, issued on Jan. 14, 2020, the entiredisclosure of which is incorporated herein by reference.

Icosahedral Dimple Patterns

In yet another embodiment, dimple patterns utilized with golf balls ofthe present disclosure are arranged in an icosahedral layout. The golfball dimple patterns are arranged in an icosahedral layout such thatthere are 20 identical sections on the golf ball. In one embodiment,each section is in the shape of a spherical triangle. The three circulararcs each represent an edge of the spherical triangle.

The dimples may be located entirely within a dimple section. Forexample, in one embodiment, the dimples may be arranged within the edgesof the spherical triangle such that no dimples intersect an edge of thespherical triangle. In another embodiment, dimples may be shared betweentwo or more dimples sections. In one aspect of this embodiment, for eachdimple that is not located entirely within a dimple section, thecentroid of the dimple is located along a side edge or at one or morevertices of the spherical triangle. In another aspect of thisembodiment, dimples shared between two sections may include dimples thatare positioned such that the centroid of the dimple does not lie along aside edge. For purposes of the present disclosure, the “centroid” of thedimple refers to the center of the dimple.

In one embodiment of the present invention, the dimple pattern withineach of the 20 identical dimple sections may be arranged such that oneor more dimples intersect an edge of the spherical triangle. In aparticular aspect of this embodiment, the edge intersected by the one ormore dimples runs through the centroid of the dimple such that half ofthe dimple is located within one spherical triangle and the other halfis located within another spherical triangle. In another aspect of thisembodiment, the edge intersected by one or more dimples does not runthrough the centroid of the dimple. That is, less than half of thedimple is located within one spherical triangle and more than half ofthe dimple is located within an adjacent spherical triangle. In oneembodiment, the dimple pattern within each of the 20 identical dimplesections includes at least three dimples that intersect an edge of thespherical triangle. In another embodiment, the dimple pattern withineach of the 20 identical dimple sections includes at least six dimplesthat intersect an edge of the spherical triangle. In another embodiment,the dimple pattern within each of the 20 identical dimple sectionsincludes at least twelve dimples that intersect an edge of the sphericaltriangle. In another embodiment, the dimple pattern within each of the20 identical dimple sections includes at least fifteen dimples thatintersect an edge of the spherical triangle.

In another embodiment, the icosahedral dimple patterns may be arrangedsuch that a dimple lies at one or more vertices of the sphericaltriangle. In this embodiment, the centroid of the dimple is located atthe vertex of the spherical triangle and a portion of the dimple islocated within five of the spherical triangles. That is, the dimplelocated at the vertex of the spherical triangle may be centered on thevertices of the spherical triangles. The dimple patterns of the presentdisclosure may include a dimple located at a single vertex of thespherical triangle. In another embodiment, the dimple patterns mayinclude a dimple located at each of two vertices of the sphericaltriangle. In still another embodiment, the dimple patterns may include adimple located at each of the three vertices of the spherical triangle.

The dimple patterns arranged in each of the dimple sections, forexample, in each of the 20 spherical triangles, are substantiallyidentical to each other. For purposes of the present disclosure, dimplepatterns are “substantially identical” if they have substantially thesame dimple arrangement (i.e., the relative positions of each of thedimples' centroids are about the same) and substantially the same dimplecharacteristics (e.g., plan shape, cross-sectional shape, diameter, edgeangle). Thus, for each dimple located entirely within a particulardimple section, for example, a particular spherical triangle, there is acorresponding dimple in each of the other 19 dimple sections. Fordimples having a centroid located along an edge of the dimple section,there is a corresponding dimple located along the same edge in the other19 dimple sections. For dimples located at the one or more vertices ofthe dimple sections, these dimples are shared between the other dimplesections.

The dimple patterns within each dimple section, for example, within eachof the 20 spherical triangles, include dimples having varying dimplediameters. In one embodiment, each dimple pattern has at least threedifferent dimple diameters, including a minimum diameter dimple, amaximum diameter dimple, and at least one additional diameter dimple.For purposes of the present disclosure, dimples having substantiallydifferent diameters include dimples on a finished ball having respectivediameters that differ by 0.005 inches or more. In another embodiment,each dimple pattern has at least four different dimple diameters,including a minimum diameter dimple, a maximum diameter dimple, and atleast two additional diameter dimples. In still another embodiment, eachdimple pattern has at least five different dimple diameters, including aminimum diameter dimple, a maximum diameter dimple, and at least threeadditional diameter dimples. In yet another embodiment, each dimplepattern has at least six different dimple diameters, including a minimumdiameter dimple, a maximum diameter dimple, and at least four additionaldiameter dimples.

In one embodiment, each dimple has a dimple diameter of about 0.030inches to about 0.200 inches. In another embodiment, each dimple has adimple diameter of about 0.050 inches to about 0.180 inches. In stillanother embodiment, each dimple has a dimple diameter of about 0.070inches to about 0.160 inches. In yet another embodiment, each dimple hasa dimple diameter of about 0.090 inches to about 0.140 inches. In someembodiments, the minimum dimple diameter is less than 0.100 inches. Forinstance, the minimum dimple diameter may be about 0.030 inches to about0.100 inches. In another embodiment, the minimum dimple diameter may beabout 0.050 inches to about 0.090 inches.

The minimum and maximum differences between any two dimple diameterswithin a dimple section may vary. In one embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.030 inches or more. In another embodiment, the minimumdifference between any two dimple diameters within a dimple section isabout 0.040 inches or more. In other embodiments, the maximum differencebetween any two dimple diameters within a dimple section is about 0.080inches or less. In another embodiment, the maximum difference betweenany two dimple diameters within a dimple section is about 0.065 inchesor less. In still another embodiment, the maximum difference between anytwo dimple diameters within a dimple section is about 0.055 inches orless. In another embodiment, the maximum difference between any twodimple diameters within a dimple section is about 0.045 inches or less.For instance, the difference between any two dimple diameters withineach dimple section is about 0.030 inches to about 0.080 inches.

In some embodiments, the dimple pattern includes at least one dimpleintersecting an edge of the dimple section. In this embodiment, at leastone dimple having the minimum dimple diameter intersects the edge of thedimple section. In another embodiment, at least one dimple having themaximum dimple diameter intersects the edge of the dimple section. Instill another embodiment, at least one dimple having neither the minimumnor maximum dimple diameter intersects the edge of the dimple section.Additionally, in some embodiments, the dimple pattern includes at leastone dimple lying at a vertex of the dimple section. In one embodiment,at least one dimple having the maximum dimple diameter is located at avertex of the dimple section. In another embodiment, at least one dimplehaving the minimum dimple diameter is located at a vertex of the dimplesection.

In one embodiment, the icosahedral dimple patterns disclosed herein maybe symmetric. For example, the dimple patterns within each dimplesection may be rotationally symmetric about the central point of eachdimple section. That is, the dimple patterns may have three-wayrotational symmetry about an axis connecting the center of the golf balland the central point of the dimple section. In another embodiment, thedimple patterns may have mirror symmetry about a central plane of eachdimple section, where the central plane is a plane containing the centerof the golf ball, the central point of the corresponding dimple section,and one vertex of the corresponding dimple section.

In one embodiment, the dimples may be arranged within each of the 20dimple sections such that there are more than four dimple free greatcircles on the outer surface of the golf ball. For example, the dimplesmay be arranged within each dimple section such that there are fivedimple free great circles on the outer surface of the golf ball. Inanother embodiment, the dimples may be arranged within each dimplesection such that there are six dimple free great circles on the outersurface of the golf ball. In other embodiments, the dimples may bearranged within each dimple section such that there are no dimple freegreat circles on the outer surface of the golf ball.

The dimples may be positioned within each of the 20 dimple sectionsaccording to any packing method known in the art so long as the dimplesections are substantially identical and meet the symmetry and surfacecoverage requirements discussed herein. For example, the dimples may bearranged within each dimple section according to the methods describedin U.S. Pat. No. 10,668,327, issued on Jun. 2, 2020, the entiredisclosure of which is incorporated herein by reference.

Dimple Dimensions

The dimples contemplated for use in the dimple patterns described abovehave a circular plan shape. However, the dimples may also have a varietyof other plan shapes, such as square, triangle, rectangle, oval, or planshapes defined by low frequency periodic functions or high frequencyperiodic functions. The diameter of a dimple having a non-circular planshape is defined by its equivalent diameter, d_(e), which may becalculated according to equation (II):

$\begin{matrix}{{d_{e} = {2\sqrt{\frac{A}{\pi}}}},} & ({II})\end{matrix}$

where d_(e) is the equivalent dimple diameter and A is the plan shapearea of the dimple. By the term, “plan shape area,” it is meant the areabased on a planar view of the dimple plan shape, such that the viewingplane is normal to an axis connecting the center of the golf ball to thepoint of the calculated surface depth. In one embodiment, the equivalentdiameters of dimples having non-circular plan shapes are the same as theranges of dimple diameters discussed above for the circular plan shapeddimples.

Diameter measurements are determined on finished golf balls according toFIG. 1 . Generally, it may be difficult to measure a dimple's diameterdue to the indistinct nature of the boundary dividing the dimple fromthe ball's undisturbed land surface. Due to the effect of paint and/orthe dimple design itself, the junction between the land surface anddimple may not be a sharp corner and is therefore indistinct. This canmake the measurement of a dimple's diameter somewhat ambiguous.

To resolve this problem, dimple diameter on a finished golf ball ismeasured according to the method shown in FIG. 1 . FIG. 1 shows a dimplehalf-profile 34, extending from a dimple centerline 31 to the landsurface outside of the dimple 33. A ball phantom surface 32 isconstructed above the dimple as a continuation of the land surface 33. Afirst tangent line T1 is then constructed at a point on the dimplesidewall that is spaced 0.003 inches radially inward from the phantomsurface 32. The first tangent line T1 intersects the phantom surface 32at a point P1, which defines a nominal dimple edge position. A secondtangent line T2 is then constructed, tangent to the phantom surface 32at P1. The edge angle is the angle between the first tangent line T1 andthe second tangent line T2. The dimple diameter is the distance betweenP1 and its equivalent point diametrically opposite along the dimpleperimeter. Alternatively, it is twice the distance between P1 and thedimple centerline 31, measured in a direction perpendicular to thedimple centerline 31. The dimple depth is the distance measured along aball radius from the phantom surface 32 of the ball to the deepest pointon the dimple. The chord plane runs through the point P1 and is normalto the dimple centerline 31. The chord depth is the distance from thechord plane to the deepest part of the dimple. The cap height is thedistance from the chord plane to the phantom surface 32 along the dimplecenterline 31. The dimple volume is the space enclosed between thephantom surface 32 and the dimple surface 34 (extended along the firsttangent line T1 until it intersects the phantom surface 32).

The dimple patterns described herein may have varying edge anglesdepending on the desired surface coverage. Optimization of the edgeangles using the equations provided herein can help reduce the flight ofthe ball while maintaining ideal trajectories. For spherical dimples,the edge angle is defined as the angle between the first tangent line T1and the second tangent line T2, as shown in FIG. 1 . In one embodiment,the average edge angle (θ_(μ)) of all the dimple edge angles on the golfball is related to the surface coverage based on the range displayed inequation (III) below:

88.8(SC)²−116.9(SC)+47.7≤θ_(μ)≤170.0(SC)²−242.5(SC)+106.6   (III),

where SC is the surface coverage and the format for SC is the decimalform of percentage (for example, 50 percent coverage is 0.50). FIG. 2 isa graphical representation of the relationship between edge angle andsurface coverage of spherical dimples according to an embodiment of thepresent disclosure. In one embodiment, the dimples may have any edgeangle falling within the range of values shown in FIG. 2 . For instance,with a desired surface coverage of about 70 percent, the average edgeangle of all the dimple edge angles on the golf ball may range fromabout 9.38 degrees to about 20.15 degrees. In another embodiment, with adesired surface coverage of about 50 percent, the average edge angle ofall the dimple edge angles on the golf ball may range from about 11.45degrees to about 27.85 degrees. In still another embodiment, with adesired surface coverage of about 30 percent, the average edge angle ofall the dimple edge angles on the golf ball may range from about 20.62degrees to about 49.15 degrees. In yet another embodiment, with adesired surface coverage of about 15 percent, the average edge angle ofall the dimple edge angles on the golf ball may range from about 32.16degrees to about 74.05 degrees. Accordingly, in some embodiments, as thesurface coverage of the dimple patterns described herein decreases, theaverage edge angles may increase.

In one embodiment, the edge angle of all the dimples within a dimplesection is substantially the same. For purposes of the presentdisclosure, edge angles on a finished golf ball are substantiallyidentical if they differ by less than about 0.25 degrees. In anotherembodiment, the dimples within a dimple section may have two differentedge angles. That is, the dimples within a dimple section may have twodifferent edge angles that differ by more than about 0.25 degrees. Instill another embodiment, the dimples within a dimple section may havethree different edge angles, where each edge angle differs from theothers by more than about 0.25 degrees.

In the embodiments where the dimples may have varying edge angles, themaximum difference in edge angle between any two dimples within a dimplesection may be about 1 degree to about 4 degrees. In one embodiment, themaximum difference in edge angle between any two dimples within a dimplesection may be about 1 degree to about 3 degrees. For example, in apreferred embodiment, the maximum difference in edge angle between anytwo dimples within a dimple section is about 1 degree.

The spherical dimples contemplated by the present disclosure may alsohave a dimple depth, chord depth, and cap height, as defined and shownin FIG. 1 . In one embodiment, when golf balls of the present disclosurehave a desired surface coverage of about 70 percent, the dimple depthsmay range from about 0.0049 inches to about 0.0146 inches. In anotherembodiment, when golf balls of the present disclosure have a desiredsurface coverage of about 50 percent, the dimple depths may range fromabout 0.0049 inches to about 0.0175 inches. In still another embodiment,when golf balls of the present disclosure have a desired surfacecoverage of about 30 percent, the dimple depths may range from about0.0063 inches to about 0.0259 inches. In yet another embodiment, whengolf balls of the present disclosure have a desired surface coverage ofabout 15 percent, the dimple depths may range from about 0.0072 inchesto about 0.0369 inches.

While the dimples have been exemplified herein as having a sphericalprofile, the dimples may have a variety of other profile shapes. Fornon-spherical dimples, the average dimple volume is related to thesurface coverage. The “dimple volume” refers to the total volumeencompassed by the dimple shape and the phantom surface of the golfball. In one embodiment, the average dimple volume (V_(μ)) of all thedimple volumes is related to the surface coverage based on the rangedisplayed in equation (IV) below:

−2.2×10⁻⁵(SC)²+7.4×10⁻⁵(SC)+1.1×10⁻⁵ ≤V_(μ)≤−2.0×10⁻⁵(SC)²+9.3×10⁻⁵(SC)+2.7×10⁻⁵   (IV),

where SC is the surface coverage and the format for SC is the decimalform of percentage, for example, 50 percent is 0.50. FIG. 3 is agraphical representation of the relationship between average dimplevolume and surface coverage of non-spherical dimples according to anembodiment of the present disclosure. In one embodiment, the dimples mayhave any average dimple volume falling within the range of values shownin FIG. 3 . For example, with a desired surface coverage of about 70percent, the average dimple volume of all the dimple volumes is about5.20×10⁻⁵ cubic inches to about 8.23×10⁻⁵ cubic inches. In anotherembodiment, with a desired surface coverage of about 50 percent, theaverage dimple volume of all the dimple volumes is about 4.25×10⁻⁵ cubicinches to about 6.85×10⁻⁵ cubic inches. In still another embodiment,with a desired surface coverage of about 30 percent, the average dimplevolume of all the dimple volumes is about 3.12×10⁻⁵ cubic inches toabout 5.31×10⁻⁵ cubic inches. In yet another embodiment, with a desiredsurface coverage of about 15 percent, the average dimple volume of allthe dimple volumes is about 2.16×10⁻⁵ cubic inches to about 4.05×10⁻⁵cubic inches. Accordingly, in some embodiments, as the surface coverageof the dimple patterns described herein decreases, the average dimplevolumes may also decrease.

Core Formulations

In one embodiment, golf balls made in accordance with the presentdisclosure have at least one core layer formed from a rubber formulationof polybutadiene rubber, butyl rubber, or a blend thereof. The at leastone core layer may be the center of the golf ball, a layer surroundingthe center (for instance, an intermediate layer), or a combinationthereof.

Polybutadiene is a homopolymer of 1,3-butadiene. The double bonds in the1,3-butadiene monomer are attacked by catalysts to grow the polymerchain and form a polybutadiene polymer having a desired molecularweight. Any suitable catalyst may be used to synthesize thepolybutadiene rubber depending upon the desired properties. In oneembodiment, a transition metal complex (for example, neodymium, nickel,or cobalt) or an alkyl metal such as alkyl lithium is used as acatalyst. Other catalysts include, but are not limited to, aluminum,boron, lithium, titanium, and combinations thereof. The catalystsproduce polybutadiene rubbers having different chemical structures. In acis-bond configuration, the main internal polymer chain of thepolybutadiene appears on the same side of the carbon-carbon double bondcontained in the polybutadiene. In a trans-bond configuration, the maininternal polymer chain is on opposite sides of the internalcarbon-carbon double bond in the polybutadiene. The polybutadiene rubbercan have various combinations of cis- and trans-bond structures. In oneembodiment, the polybutadiene rubber has a 1,4 cis-bond content of atleast 40%. In another embodiment, the polybutadiene rubber has a 1,4cis-bond content of greater than 80%. In still another embodiment, thepolybutadiene rubber has a 1,4 cis-bond content of greater than 90%. Ingeneral, polybutadiene rubbers having a high 1,4 cis-bond content havehigh tensile strength.

The polybutadiene rubber may have a relatively high or low Mooneyviscosity. Generally, polybutadiene rubbers of higher molecular weightand higher Mooney viscosity have better resiliency than polybutadienerubbers of lower molecular weight and lower Mooney viscosity. However,as the Mooney viscosity increases, the milling and processing of thepolybutadiene rubber generally becomes more difficult. Blends of highand low Mooney viscosity polybutadiene rubbers may be prepared as isdescribed in Voorheis et al., U.S. Pat. Nos. 6,982,301 and 6,774,187,the disclosures of which are hereby incorporated by reference, and usedin accordance with this invention. In general, the lower limit of Mooneyviscosity may be 30 or 35 or 40 or 45 or 50 or 55 or 60 or 70 or 75 andthe upper limit may be 80 or 85 or 90 or 95 or 100 or 105 or 110 or 115or 120 or 125 or 130.

Examples of commercially available polybutadiene rubbers that can beused in accordance with this invention, include, but are not limited to,BR 01 and BR 1220, available from BST Elastomers of Bangkok, Thailand;SE BR 1220LA and SE BR1203, available from DOW Chemical Co of Midland,Mich.; BUDENE 1207, 1207s, 1208, and 1280 available from Goodyear, Incof Akron, Ohio; BR 01, 51 and 730, available from Japan Synthetic Rubber(JSR) of Tokyo, Japan; BUNA CB 21, CB 22, CB 23, CB 24, CB 25, CB 29IVIES, CB 60, CB Nd 60, CB 55 NF, CB 70 B, CB KA 8967, and CB 1221,available from Lanxess Corp. of Pittsburgh. Pa.; BR1208, available fromLG Chemical of Seoul, South Korea; UBEPOL BR130B, BR150, BR150B, BR150L,BR230, BR360L, BR710, and VCR617, available from UBE Industries, Ltd. ofTokyo, Japan; EUROPRENE NEOCIS BR 60, INTENE 60 AF and P30AF, andEUROPRENE BR HV80, available from Polimeri Europa of Rome, Italy; AFDENE50 and NEODENE BR40, BR45, BR50 and BR60, available from Karbochem (PTY)Ltd. of Bruma, South Africa; KBR 01, NdBr 40, NdBR-45, NdBr 60, KBR710S, KBR 710H, and KBR 750, available from Kumho Petrochemical Co.,Ltd. Of Seoul, South Korea; DIENE 55NF, 70AC, and 320 AC, available fromFirestone Polymers of Akron, Ohio; and PBR-Nd Group II and Group III,available from Nizhnekamskneftekhim, Inc. of Nizhnekamsk, TartarstanRepublic.

In another embodiment, golf balls made in accordance with the presentdisclosure have at least one core layer formed from butyl rubber. Butylrubber is an elastomeric copolymer of isobutylene and isoprene. Butylrubber is an amorphous, non-polar polymer with good oxidative andthermal stability, good permanent flexibility and high moisture and gasresistance. Generally, butyl rubber includes copolymers of about 70% to99.5% by weight of an isoolefin, which has about 4 to 7 carbon atoms,for example, isobutylene, and about 0.5% to 30% by weight of aconjugated multiolefin, which has about 4 to 14 carbon atoms, forexample, isoprene. The resulting copolymer contains about 85% to about99.8% by weight of combined isoolefin and 0.2% to 15% of combinedmultiolefin. A commercially available butyl rubber includes Bayer Butyl301 manufactured by Bayer AG.

In some embodiments, the polybutadiene rubber and the butyl rubber areblended together to form at least one core layer. In this embodiment,the core layer may include a blend of polybutadiene rubber and butylrubber in a ratio of about 10:90 to about 90:10. In another embodiment,the core layer may include a blend of polybutadiene rubber and butylrubber in a ratio of about 30:70 to about 70:30. In still anotherembodiment, the core layer may include a blend of polybutadiene rubberand butyl rubber in a ratio of about 40:60 to about 60:40.

In other embodiments, the polybutadiene rubber and/or butyl rubber maybe blended with other elastomers including, but not limited to,polyisoprene, ethylene propylene rubber (“EPR”), styrene-butadienerubber, styrenic block copolymer rubbers (such as “SI”, “SIS”, “SB”,“SBS”, “SIBS”, and the like, where “S” is styrene, “I” is isobutylene,and “B” is butadiene), polyalkenamers such as, for example,polyoctenamer, halobutyl rubber, polystyrene elastomers, polyethyleneelastomers, polyurethane elastomers, polyurea elastomers,metallocene-catalyzed elastomers and plastomers, copolymers ofisobutylene and p-alkylstyrene, halogenated copolymers of isobutyleneand p-alkylstyrene, copolymers of butadiene with acrylonitrile,polychloroprene, alkyl acrylate rubber, chlorinated isoprene rubber,acrylonitrile chlorinated isoprene rubber, and combinations of two ormore thereof.

In one embodiment, the amount of polybutadiene rubber present in thecore layer is related to the surface coverage of dimples on the outercover. For example, the amount of polybutadiene rubber present in thecore layer and the surface coverage of dimples have the relationshipshown in equation (V) below:

$\begin{matrix}{\frac{BR}{1 - {SC}} \leq 2.} & (V)\end{matrix}$

where BR represents the weight percent of polybutadiene rubber, indecimal form, based on the total weight of rubber in the core layercomposition, and 0≤BR≤1; and SC represents the surface coverage in thedecimal form of percentage, and 0<SC<1. According to formula (V), a golfball made in accordance with the present disclosure and having a surfacecoverage of about 70 percent (SC=0.70) may include at least one corelayer having a weight percentage of polybutadiene rubber of about 60percent or less (BR≤0.60). In another embodiment, a golf ball made inaccordance with the present disclosure and having a surface coverage ofabout 65 percent (SC=0.65) may include at least one core layer having aweight percentage of polybutadiene rubber of about 70 percent or less(BR≤0.70). In another embodiment, a golf ball made in accordance withthe present disclosure and having a surface coverage of about 60 percent(SC=0.60) may include at least one core layer having a weight percentageof polybutadiene rubber of about 80 percent or less (BR≤0.80). In stillanother embodiment, a golf ball made in accordance with the presentdisclosure and having a surface coverage of about 50 percent (SC=0.50)may include at least one core layer having a weight percentage ofpolybutadiene rubber of about 100 percent or less (BR≤1).

In another embodiment, the amount of polybutadiene rubber present in thecore layer and the surface coverage of dimples have the relationshipshown in formula (VI) below:

$\begin{matrix}{\frac{BR}{1 - {SC}} \leq 1.75} & ({VI})\end{matrix}$

where BR represents the weight percent of polybutadiene rubber, indecimal form, based on the total weight of rubber in the core layercomposition, and 0≤BR≤1; and SC represents the surface coverage in thedecimal form of percentage, and 0<SC<1. For example, a golf ball made inaccordance with the present disclosure and having a surface coverage ofabout 70 percent (SC=0.70) may include at least one core layer having aweight percentage of polybutadiene rubber of about 52.5 percent or less(BR≤0.525). In another embodiment, a golf ball made in accordance withthe present disclosure and having a surface coverage of about 65 percent(SC=0.65) may include at least one core layer having a weight percentageof polybutadiene rubber of about 61.3 percent or less (BR≤0.613). Inanother embodiment, a golf ball made in accordance with the presentdisclosure and having a surface coverage of about 60 percent (SC=0.60)may include at least one core layer having a weight percentage ofpolybutadiene rubber of about 70 percent or less (BR≤0.70). In stillanother embodiment, a golf ball made in accordance with the presentdisclosure and having a surface coverage of about 50 percent (SC=0.50)may include at least one core layer having a weight percentage ofpolybutadiene rubber of about 87.5 percent or less (BR≤0.875).

In still another embodiment, the amount of polybutadiene rubber presentin the core layer and the surface coverage of dimples have therelationship shown in formula (VII) below:

$\begin{matrix}{\frac{BR}{1 - {SC}} \leq 1.5} & ({VII})\end{matrix}$

where BR represents the weight percent of polybutadiene rubber, indecimal form, based on the total weight of rubber in the core layercomposition, and 0≤BR≤1; and SC represents the surface coverage in thedecimal form of percentage, and 0<SC<1. For example, a golf ball made inaccordance with the present disclosure and having a surface coverage ofabout 70 percent (SC=0.70) may include at least one core layer having aweight percentage of polybutadiene rubber of about 45 percent or less(BR≤0.45). In another embodiment, a golf ball made in accordance withthe present disclosure and having a surface coverage of about 65 percent(SC=0.65) may include at least one core layer having a weight percentageof polybutadiene rubber of about 52.5 percent or less (BR≤0.525). Inanother embodiment, a golf ball made in accordance with the presentdisclosure and having a surface coverage of about 60 percent (SC=0.60)may include at least one core layer having a weight percentage ofpolybutadiene rubber of about 60 percent or less (BR≤0.60). In stillanother embodiment, a golf ball made in accordance with the presentdisclosure and having a surface coverage of about 50 percent (SC=0.50)may include at least one core layer having a weight percentage ofpolybutadiene rubber of about 75 percent or less (BR≤0.75). In yetanother embodiment, a golf ball having a surface coverage of about 40percent (SC=0.40) may include at least one core layer having a weightpercentage of polybutadiene rubber of about 90 percent or less(BR≤0.90).

In yet another embodiment, the relationship between the amount ofpolybutadiene rubber in the core layer and the surface coverage ofdimples may include a size modifier and a weight modifier to account forthe size and weight of the finished golf ball. For example, therelationship between the weight percentage of polybutadiene rubber inthe core and the surface coverage of dimples, including a size modifierand a weight modifier, is shown in formula (VIII) below:

$\begin{matrix}{{{\left( \frac{w}{1.62} \right)^{3}\left( \frac{1.68}{d} \right)^{8}\left( \frac{BR}{1 - {SC}} \right)} \leq 2.},\left( {{or}1.75{or}1.5} \right)} & ({VIII})\end{matrix}$

where BR represents the weight percent of polybutadiene rubber, indecimal form, based on the total weight of rubber in the core layercomposition, and 0≤BR≤1; SC represents the surface coverage in thedecimal form of percentage, and 0<SC<1; d is the diameter of the golfball in inches; and w is the weight of the finished golf ball in ounces.According to the Rules of Golf as approved by the USGA, a golf ball maynot have a weight in excess of 1.620 ounces (45.93 g) or a diameter ofless than 1.680 inches (42.67 mm). However, the USGA rules do not set aminimum weight or a maximum diameter for the ball. In some embodiments,a golf ball having a decreased weight and/or an increased diameter maybe made to decrease the overall distance a ball travels at a given swingspeed while maintaining a high-performance trajectory during flight.Accordingly, the diameter of golf balls prepared according to thepresent disclosure may range from about 1.680 inches to about 1.800inches. In another embodiment, the diameter of the golf balls may rangefrom about 1.688 inches to about 1.800 inches. In still anotherembodiment, the diameter of the golf balls may range from about 1.690inches to about 1.740 inches. In yet another embodiment, the diameter ofthe golf balls may range from 1.695 inches to about 1.725 inches. Theweight of the golf balls prepared according to the present disclosuremay range from about 1.39 ounces to about 1.62 ounces. For example, theweight of the golf balls may range from about 1.45 ounces to about 1.58ounces.

Aerodynamic Characteristics

As described above, the golf balls of the present disclosure combine acore formulation having a low percentage of polybutadiene or butylrubber with a less aerodynamic dimple pattern (for example, a lowsurface coverage dimple pattern) to achieve a reduction in overalldistance when compared to a conventional golf ball. This combination oflow surface coverage and low polybutadiene or butyl rubber usage helpsto reduce the flight of the ball while also providing improvedaerodynamic consistency and maintaining the appearance of ahigh-performance trajectory.

In some embodiments, the golf balls described herein have reducedspeeds, which result in reduced flight. The speed of golf balls made inaccordance with the present disclosure is related to the surfacecoverage of dimples on the outer cover. For example, the initialvelocity of a finished golf ball made in accordance with the presentdisclosure may be related to the surface coverage according to formula(IX) shown below:

$\begin{matrix}{\frac{IV}{1 - {SC}} \leq 700} & ({IX})\end{matrix}$

where IV represents the initial velocity of the finished golf ball inft/sec and SC is the surface coverage in the decimal form of percentage,and 0<SC<1. For instance, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 70 percent(SC=0.70) may have an initial velocity of about 210 ft/sec or less(IV≤210). In another embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 65 percent(SC=0.65) may have an initial velocity of about 245 ft/sec or less(IV≤245). In another embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 60 percent(SC=0.60) may have an initial velocity of about 280 ft/sec or less(IV≤280). In still another embodiment, a golf ball made in accordancewith the present disclosure and having a surface coverage of about 50percent (SC=0.50) may have an initial velocity of about 350 ft/sec orless (IV≤350). In yet another embodiment, a golf ball having a surfacecoverage of about 40 percent (SC=0.40) may have an initial velocity ofabout 420 ft/sec or less (IV≤420).

In another embodiment, the initial velocity of a finished golf ball madein accordance with the present disclosure may be related to the surfacecoverage according to formula (X) shown below:

$\begin{matrix}{\frac{IV}{1 - {SC}} \leq 600} & (X)\end{matrix}$

where IV represents the initial velocity of the finished golf ball inft/sec and SC is the surface coverage in the decimal form of percentage,and 0<SC<1. In one embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 70 percent(SC=0.70) may have an initial velocity of about 180 ft/sec or less(IV≤180). In another embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 65 percent(SC=0.65) may have an initial velocity of about 210 ft/sec or less(IV≤210). In another embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 60 percent(SC=0.60) may have an initial velocity of about 240 ft/sec or less(IV≤240). In still another embodiment, a golf ball made in accordancewith the present disclosure and having a surface coverage of about 50percent (SC=0.50) may have an initial velocity of about 300 ft/sec orless (IV≤300). In yet another embodiment, a golf ball having a surfacecoverage of about 40 percent (SC=0.40) may have an initial velocity ofabout 360 ft/sec or less (IV≤360).

In still another embodiment, the initial velocity of a finished golfball made in accordance with the present disclosure may be related tothe surface coverage according to formula (XI) shown below:

$\begin{matrix}{\frac{IV}{1 - {SC}} \leq 500} & ({XI})\end{matrix}$

where IV represents the initial velocity of the finished golf ball inft/sec and SC is the surface coverage in the decimal form of percentage,and 0<SC<1. In one embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 70 percent(SC=0.70) may have an initial velocity of about 150 ft/sec or less(IV≤150). In another embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 65 percent(SC=0.65) may have an initial velocity of about 175 ft/sec or less(IV≤175). In another embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 60 percent(SC=0.60) may have an initial velocity of about 200 ft/sec or less(IV≤200). In still another embodiment, a golf ball made in accordancewith the present disclosure and having a surface coverage of about 50percent (SC=0.50) may have an initial velocity of about 250 ft/sec orless (IV≤250). In yet another embodiment, a golf ball having a surfacecoverage of about 40 percent (SC=0.40) may have an initial velocity ofabout 300 ft/sec or less (IV≤300).

In yet another embodiment, the relationship between the initial velocityof a finished golf ball and the surface coverage of dimples may includea size modifier and a weight modifier to account for the size and weightof the finished golf ball. For instance, the relationship between theinitial velocity of a finished golf ball made in accordance with thepresent disclosure and the surface coverage, including the size modifierand the weight modifier, is shown in formula (XII) below:

$\begin{matrix}{{{\left( \frac{w}{1.62} \right)^{3}\left( \frac{1.68}{d} \right)^{8}\left( \frac{IV}{1 - {SC}} \right)} \leq 700},\left( {{or}600{or}500} \right)} & ({XII})\end{matrix}$

where IV represents the initial velocity of the finished golf ball inft/sec, SC represents the surface coverage in the decimal form ofpercentage and 0<SC<1, d is the diameter of the golf ball in inches, andw is the weight of the finished golf ball in ounces. The diameter andthe weight of the finished golf ball may vary according to the rangesdiscussed above with respect to formula (VIII).

In some embodiments, the coefficient of restitution (COR) of golf ballsmade in accordance with the present disclosure is also related to thesurface coverage of dimples on the outer cover. A golf ball's COR is theratio of the relative velocity of the ball after direct impact to thatbefore impact. One way to measure the COR is to propel a ball at a givenspeed against a hard massive surface and measure its incoming velocityand outgoing velocity. The COR is defined as the ratio of the outgoingvelocity to incoming velocity of a rebounding ball and is expressed as adecimal. The COR can vary from zero to one, with one being equivalent toan elastic collision and zero being equivalent to an inelasticcollision. The COR measurements discussed herein are measured at 125ft/sec incoming ball velocity

In one embodiment, the COR of a finished golf ball made in accordancewith the present disclosure may be related to the surface coverageaccording to formula (XIII) shown below:

$\begin{matrix}{\frac{COR}{1 - {SC}} \leq 2.} & ({XIII})\end{matrix}$

where COR represents the coefficient of restitution and 0<COR<1, and SCrepresents the surface coverage in the decimal form of percentage and0<SC<1. In this embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 70 percent(SC=0.70) may have a COR of about 0.600 or less (COR≤0.600). In anotherembodiment, a golf ball made in accordance with the present disclosureand having a surface coverage of about 65 percent (SC=0.65) may have aCOR of about 0.700 or less (COR≤0.700). In another embodiment, a golfball made in accordance with the present disclosure and having a surfacecoverage of about 60 percent (SC=0.60) may have a COR of about 0.800 orless (COR≤0.800). In still another embodiment, a golf ball made inaccordance with the present disclosure and having a surface coverage ofabout 55 percent (SC=0.55) may have a COR of about 0.900 or less(COR≤0.900).

In another embodiment, the COR of a finished golf ball made inaccordance with the present disclosure may be related to the surfacecoverage according to formula (XIV) shown below:

$\begin{matrix}{\frac{COR}{1 - {SC}} \leq 1.75} & ({XIV})\end{matrix}$

where COR represents the coefficient of restitution and 0<COR<1, and SCrepresents the surface coverage in the decimal form of percentage and0<SC<1. In this embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 70 percent(SC=0.70) may have a COR of about 0.525 or less (COR≤0.525). In anotherembodiment, a golf ball made in accordance with the present disclosureand having a surface coverage of about 65 percent (SC=0.65) may have aCOR of about 0.613 or less (COR≤0.613). In another embodiment, a golfball made in accordance with the present disclosure and having a surfacecoverage of about 60 percent (SC=0.60) may have a COR of about 0.700 orless (COR≤0.700). In still another embodiment, a golf ball made inaccordance with the present disclosure and having a surface coverage ofabout 55 percent (SC=0.55) may have a COR of about 0.788 or less(COR≤0.788). In yet another embodiment, a golf ball made in accordancewith the present disclosure and having a surface coverage of about 50percent (SC=0.50) may have a COR of about 0.875 or less (COR≤0.875).

In still another embodiment, the COR of a finished golf ball made inaccordance with the present disclosure may be related to the surfacecoverage according to formula (XV) shown below:

$\begin{matrix}{\frac{COR}{1 - {SC}} \leq 1.5} & ({XV})\end{matrix}$

where COR represents the coefficient of restitution and 0<COR<1, and SCrepresents the surface coverage in the decimal form of percentage and0<SC<1. In this embodiment, a golf ball made in accordance with thepresent disclosure and having a surface coverage of about 70 percent(SC=0.70) may have a COR of about 0.450 or less (COR≤0.450). In anotherembodiment, a golf ball made in accordance with the present disclosureand having a surface coverage of about 65 percent (SC=0.65) may have aCOR of about 0.525 or less (COR≤0.525). In another embodiment, a golfball made in accordance with the present disclosure and having a surfacecoverage of about 60 percent (SC=0.60) may have a COR of about 0.600 orless (COR≤0.600). In still another embodiment, a golf ball made inaccordance with the present disclosure and having a surface coverage ofabout 55 percent (SC=0.55) may have a COR of about 0.675 or less(COR≤0.675). In yet another embodiment, a golf ball made in accordancewith the present disclosure and having a surface coverage of about 50percent (SC=0.50) may have a COR of about 0.750 or less (COR≤0.750).

In yet another embodiment, the relationship between the COR of afinished golf ball and the surface coverage of dimples may include asize modifier and a weight modifier to account for the size and weightof the finished golf ball. For instance, the relationship between theCOR of a finished golf ball made in accordance with the presentdisclosure and the surface coverage, including the size modifier and theweight modifier, is shown in formula (XVI) below:

$\begin{matrix}{{{\left( \frac{w}{1.62} \right)^{3}\left( \frac{1.68}{d} \right)^{8}\left( \frac{COR}{1 - {SC}} \right)} \leq 2.},\left( {{or}1.75{or}1.5} \right)} & ({XVI})\end{matrix}$

where COR represents the coefficient of restitution and 0<COR<1, SCrepresents the surface coverage in the decimal form of percentage and0<SC<1, d is the diameter of the golf ball in inches, and w is theweight of the finished golf ball in ounces. The diameter and the weightof the finished golf ball may vary according to the ranges discussedabove with respect to formula (VIII).

In some embodiments, the golf balls made in accordance with the presentdisclosure have a maximum distance of about 95 percent or less of themaximum distance allowed in accordance with USGA-TPX3006, Revision 2.0.0(“USGA distance rules”). In one embodiment, the maximum distance of agolf ball of the present invention is about 90 percent or less of themaximum distance allowed in accordance with USGA distance rules. Inanother embodiment, a golf ball of the present invention has a maximumdistance of about 85 percent or less of the maximum distance allowed inaccordance with USGA distance rules.

In other embodiments, the golf balls made in accordance with the presentdisclosure achieve a reduction in overall distance of at least about 10yards when compared to a similar conventional golf ball. In anotherembodiment, a golf ball of the present invention achieves a reduction inoverall distance of at least about 15 yards when compared to a similarconventional golf ball. In still another embodiment, a golf ball of thepresent invention achieves a reduction in overall distance of at leastabout 20 yards when compared to a similar conventional golf ball. In yetanother embodiment, a golf ball of the present invention achieves areduction in overall distance of about 25 yards when compared to asimilar conventional golf ball.

Golf Ball Construction

Golf balls having various constructions may be made in accordance withthe present disclosure. For example, golf balls having two-piece,three-piece, four-piece, and five-piece constructions may be made. Thegolf balls may contain cores and covers having single or multiplelayers. The term, “layer” as used herein means generally any sphericalportion of the golf ball. In one embodiment, the golf balls of thepresent disclosure may be a two-piece golf ball having a core and acover. In another embodiment, the golf balls of the present disclosuremay be a three-piece golf ball having a dual-core (including a center orinner core and a layer disposed thereon) and a cover. In still anotherembodiment, the golf balls of the present disclosure may be a four-piecegolf ball having a dual-core as described above and a dual-cover(including an inner cover and outer cover). In yet another embodiment,the golf balls of the present disclosure may be a five-piece golf ballhaving a dual-core, intermediate layer, and dual-cover. As used herein,the term, “intermediate layer,” refers to a layer of the ball disposedbetween the core and cover. The intermediate layer may be considered anouter core layer, or inner cover layer, or any other layer disposedbetween the inner core and outer cover of the ball. The intermediatelayer also may be referred to as a casing or mantle layer.

Different materials may be used in the construction of golf ballsaccording to the present disclosure. For example, the cover of the ballmay be made of a thermoset or thermoplastic, a castable or non-castablepolyurethane and polyurea, an ionomer resin, balata, or any othersuitable cover material known to those skilled in the art. In oneembodiment, the cover of the ball may be made of a polyurethane.Conventional and non-conventional materials may be used for forming coreand intermediate layers of the ball including, for instance,polybutadiene, butyl rubber, and other rubber-based core formulations,ionomer resins, highly neutralized polymers, and the like.

The golf balls of the present disclosure may be formed using a varietyof application techniques. For example, the golf ball layers may beformed using compression molding, flip molding, injection molding,retractable pin injection molding, reaction injection molding (RIM),liquid injection molding (LIM), casting, vacuum forming, powder coating,flow coating, spin coating, dipping, spraying, and the like.Conventionally, compression molding and injection molding are applied tothermoplastic materials, whereas RIM, liquid injection molding, andcasting are employed on thermoset materials.

The golf balls described and claimed herein are not to be limited inscope by the specific embodiments herein disclosed, since theseembodiments are intended as illustrations of several aspects of thedisclosure. Any equivalent embodiments are intended to be within thescope of this disclosure. Indeed, various modifications of the device inaddition to those shown and described herein will become apparent tothose skilled in the art from the foregoing description. Suchmodifications are also intended to fall within the scope of the appendedclaims. All patents and patent applications cited in the foregoing textare expressly incorporated herein by reference in their entirety. Anysection headings herein are provided only for consistency with thesuggestions of 37 C.F.R. § 1.77 or otherwise to provide organizationalqueues. These headings shall not limit or characterize the invention(s)set forth herein.

What is claimed is:
 1. A golf ball comprising: a core layer comprising arubber formulation of polybutadiene rubber, butyl rubber, or a blendthereof, and a cover layer comprising a plurality of dimples disposedthereon, wherein the dimples are arranged in an octahedral patterncomprising eight substantially identical dimple sections, wherein eachdimple section is defined by a spherical triangle, wherein the dimplesin each of the eight substantially identical dimple sections have acorresponding dimple diameter and a corresponding edge angle and thedimples in each of the eight substantially identical dimple sectionscomprise: (i) at least three different dimple diameters including aminimum dimple diameter, a maximum dimple diameter, and at least oneadditional dimple diameter, wherein each of the at least three differentdimple diameters range from about 0.030 inches to about 0.200 inches,and (ii) substantially identical edge angles, and wherein the patternhas a surface coverage of about 65 percent or less, and wherein thesurface coverage is related to an amount of the rubber formulationaccording to the following equation: $\frac{BR}{1 - {SC}} \leq 2.$ whereSC is the surface coverage in the decimal form of percentage and 0<SC<1,and BR is the weight percent of polybutadiene rubber, in decimal form,based on the total weight of rubber in the rubber formulation and0≤BR≤1.
 2. The golf ball of claim 1, wherein the golf ball has acoefficient of restitution and the coefficient of restitution is relatedto the surface coverage according to the following equation:$\frac{COR}{1 - {SC}} \leq 2.$ where COR is the coefficient ofrestitution and 0<COR<1, and SC is the surface coverage in the decimalform of percentage and 0<SC<1.
 3. The golf ball of claim 1, wherein theaverage of all the edge angles (θ_(μ)) is related to the surfacecoverage according to the following equation:88.8(SC)²−116.9(SC)+47.7≤θ_(μ)≤170.0(SC)²−242.5(SC)+106.6 where SC isthe surface coverage in the decimal form of percentage and 0<SC<1. 4.The golf ball of claim 1, wherein the rubber formulation comprises ablend of polybutadiene rubber and butyl rubber in a ratio of about 40:60to about 60:40.
 5. The golf ball of claim 1, wherein the golf ballcomprises an initial velocity and the initial velocity is related to thesurface coverage according to the following equation:$\frac{IV}{1 - {SC}} \leq 500$ where IV is the initial velocity inft/sec and SC is the surface coverage in the decimal form of percentageand 0<SC<1.
 6. The golf ball of claim 1, wherein the pattern results inat least four dimple free great circles on the golf ball.
 7. A golf ballcomprising: a core layer comprising a rubber formulation ofpolybutadiene rubber, butyl rubber, or a blend thereof, and a coverlayer comprising a plurality of dimples disposed thereon, wherein thedimples are arranged in an octahedral pattern comprising eightsubstantially identical dimple sections, wherein each dimple section isdefined by a spherical triangle, wherein the dimples in each of theeight substantially identical dimple sections have a correspondingdimple diameter and a corresponding edge angle and the dimples in eachof the eight substantially identical dimple sections comprise: (i) atleast three different dimple diameters including a minimum dimplediameter, a maximum dimple diameter, and at least one additional dimplediameter, wherein each of the at least three different dimple diametersrange from about 0.030 inches to about 0.200 inches, and (ii)substantially identical edge angles, and wherein the pattern has asurface coverage of about 60 percent or less, and wherein the surfacecoverage is related to an amount of the rubber formulation according tothe following equation: $\frac{BR}{1 - {SC}} \leq 1.75$ where SC is thesurface coverage in the decimal form of percentage and 0<SC<1, and BR isthe weight percent of polybutadiene rubber, in decimal form, based onthe total weight of rubber in the rubber formulation and 0≤BR≤1.
 8. Thegolf ball of claim 7, wherein the rubber formulation comprises a blendof polybutadiene rubber and butyl rubber.
 9. The golf ball of claim 7,wherein the golf ball has a coefficient of restitution (COR) and the CORis related to the surface coverage according to the following equation:$\frac{COR}{1 - {SC}} \leq 2.$ where COR is the coefficient ofrestitution and 0<COR<1 and SC is the surface coverage in the decimalform of percentage and 0<SC<1.
 10. The golf ball of claim 7, wherein thegolf ball comprises an initial velocity and the initial velocity isrelated to the surface coverage according to the following equation:$\frac{IV}{1 - {SC}} \leq 700$ where IV is the initial velocity inft/sec and SC is the surface coverage in the decimal form of percentageand 0<SC<1.
 11. The golf ball of claim 7, wherein the rubber formulationfurther comprises polyisoprene, ethylene propylene rubber,styrene-butadiene rubber, or combinations of two or more thereof. 12.The golf ball of claim 7, wherein the rubber formulation comprisespolybutadiene rubber having a 1,4 cis-bond content of greater than 80%.13. The golf ball of claim 7, wherein the pattern has a surface coverageof about 50 percent or less.
 14. The golf ball of claim 7, wherein theaverage of all the edge angles (θ_(μ)) is related to the surfacecoverage according to the following equation:88. 8(SC)²−116.9(SC)+47.7≤θ_(μ)≤170.0(SC)²−242.5(SC)+106.6 where SC isthe surface coverage in the decimal form of percentage and 0<SC<1.
 15. Agolf ball comprising: a core layer comprising a rubber formulation, therubber formulation comprising a blend of polybutadiene rubber and butylrubber, and a cover layer comprising a plurality of dimples disposedthereon, wherein the dimples are arranged in an octahedral patterncomprising eight substantially identical dimple sections, wherein eachdimple section is defined by a spherical triangle, wherein the dimplesin each of the eight substantially identical dimple sections have acorresponding dimple diameter and a corresponding edge angle and thedimples in each of the eight substantially identical dimple sectionscomprise: (i) four or more different dimple diameters including aminimum dimple diameter, a maximum dimple diameter, and at least twoadditional dimple diameters, wherein each of the four or more differentdimple diameters range from about 0.050 inches to about 0.180 inches,and (ii) substantially identical edge angles, and wherein the patternhas a surface coverage of about 65 percent or less, and wherein thesurface coverage is related to an amount of the rubber formulationaccording to the following equation: $\frac{BR}{1 - {SC}} \leq 2.$ whereSC is the surface coverage in the decimal form of percentage and 0<SC<1,and BR is the weight percent of polybutadiene rubber, in decimal form,based on the total weight of rubber in the rubber formulation and0≤BR≤1.
 16. The golf ball of claim 15, wherein the pattern results in atleast four dimple free great circles on the golf ball.
 17. The golf ballof claim 15, wherein the pattern has a surface coverage of about 60percent or less.
 18. The golf ball of claim 15, wherein the golf ballhas a coefficient of restitution (COR) and the COR is related to thesurface coverage according to the following equation:$\frac{COR}{1 - {SC}} \leq 2.$ where COR is the coefficient ofrestitution and 0<COR<1 and SC is the surface coverage in the decimalform of percentage and 0<SC<1.
 19. The golf ball of claim 15, whereinthe golf ball comprises an initial velocity and the initial velocity isrelated to the surface coverage according to the following equation:$\frac{IV}{1 - {SC}} \leq 700$ where IV is the initial velocity inft/sec and SC is the surface coverage in the decimal form of percentageand 0<SC<1.
 20. The golf ball of claim 15, wherein the pattern hasthree-way rotational symmetry about the center of each substantiallyidentical dimple section.